A few individuals with intermediate morphology always appeared in the sympatric distributions of Gentiana straminea and G.siphonantha.These intermediate individuals were hypothesized to be the hybrids of two species a...A few individuals with intermediate morphology always appeared in the sympatric distributions of Gentiana straminea and G.siphonantha.These intermediate individuals were hypothesized to be the hybrids of two species after a careful evaluation of their morphological characteristics.To test this hypothesis,sequence comparison of the internal transcribed spacer(ITS)regions of the nuclear ribosomal and trnS(GCU)-trnG(UCC)intergenic spacer region of the chloroplast DNA from Gentiana straminea,G.siphonantha and the putative hybrids was performed.The results suggest that most intermediate individuals were the natural hybrids between G.straminea and G.siphonantha.In addition,we examined the sequence variation among the individuals of both parent species and analyzed the possibility leading to the incongruent identification in some individuals based on morphologic and molecular evidences,respectively.The intraspecific diversification of DNA fragments within both parent species and their high variability in hybrid swarms probably resulted from chloroplast genome recombination and incomplete lineage sorting during the early stages of speciation origin of the parent species.展开更多
基金The project was supported by the National Natural Science Foundation of China(Grant No.30572329).
文摘A few individuals with intermediate morphology always appeared in the sympatric distributions of Gentiana straminea and G.siphonantha.These intermediate individuals were hypothesized to be the hybrids of two species after a careful evaluation of their morphological characteristics.To test this hypothesis,sequence comparison of the internal transcribed spacer(ITS)regions of the nuclear ribosomal and trnS(GCU)-trnG(UCC)intergenic spacer region of the chloroplast DNA from Gentiana straminea,G.siphonantha and the putative hybrids was performed.The results suggest that most intermediate individuals were the natural hybrids between G.straminea and G.siphonantha.In addition,we examined the sequence variation among the individuals of both parent species and analyzed the possibility leading to the incongruent identification in some individuals based on morphologic and molecular evidences,respectively.The intraspecific diversification of DNA fragments within both parent species and their high variability in hybrid swarms probably resulted from chloroplast genome recombination and incomplete lineage sorting during the early stages of speciation origin of the parent species.
